From the archive: Just so you know, this article is more than 3 years old.
Words: Bridget Leathley
In 1931, US industrial safety pioneer Herbert W Heinrich suggested that "an injury invariably results from a complicated sequence of factors, the last one of which being the accident itself". Heinrich presented his idea as a line of dominos -- the final piece, representing the injury, fell because the previous one, tripping on the building material, did too. The trip occurred because the injured person created an unsafe condition -- that of not paying attention to his environment -- and they did this because of their "ancestry and social environment". In our example, Fred is part of the generation that finds it hard not to respond to their phones, and the work environment around him has not tempered this impulse.
In the 1980s Frank Bird, inventor of the safety triangle, updated the model to place lack of management control as the first domino in the sequence -- for example, lack of control over building materials storage. Other theories suggested that a single row of dominos couldn't represent the multiple contributing factors in an accident.
By the end of the 1990s, psychologist James Reason's Swiss cheese model (SCM) had become popular, showing an accident trajectory with a sequence of barriers which could prevent an accident but which, due to latent conditions, allow an accident to happen. This is represented by slices of cheese (the barriers) each with holes representing failings. A "hole" in each barrier allowed the accident to occur, and fixing any one of them would have prevented the accident. For convenience, in analysing such accidents we then say there were multiple causes, usually categorised as immediate (tripping), underlying (obstacle on path, not paying attention) and root causes (the failure of supervision and management on the worksite which should have prevented the obstacle and discouraged Fred's non-conformant behaviour).
Though multiple causation has become a convenient way of thinking about accidents, an opposing school of thought is summarised by the writings of Paul Difford, research director at the Institute of Industrial Accident Investigators, stating an accident has only one cause -- in this case, Fred being distracted. Twenty people had walked down the same path and had managed to avoid the obstacle, hence the one cause is the distraction. It may be technically correct to call something a "cause" if it is chronologically the final step that led to the injury but, arguably, the single-cause approach is of limited use. People will be distracted, they will make mistakes, they will forget things, so an employer has to create a working environment that is as safe, and as forgiving of errors and violations, as reasonably practicable.
In civil cases, the claimant who has been hurt at work has to prove that a negligent action of the organisation (or of an employee) caused the injury. Asbestos cases show how complicated this can be. In the case of multiple employers that have exposed a worker to asbestos, a ruling in 2000 determined that damages should be split between all of them, proportioned according to the length of time the claimant worked for each employer. But later cases made this division of causality less certain. Some cases resorted to damages being awarded against a single employer that could be shown to have made a material contribution to the risk.
In criminal cases there is no need to prove that an act or omission caused an injury. The Health and Safety at Work Act requires employers to ensure, so far as is reasonably practicable, the health, safety and welfare at work of all their employees. The law does not directly trouble itself with whether the employer caused damage to health, safety or welfare, just whether the employer could have "ensured" those three standards.
It is a legal requirement to provide a safe place of work and a safe system of work, so though the single-cause school might argue that neither the obstacle on the path in our earlier example nor poor site management were the causes of the accident, the breach of the requirement to provide a safe workplace would be demonstrable through the accident occurring. If the final link in the chain was the employee being distracted by a phone call, this does not remove the liability of the employer for permitting obstacles on the path. The law applies the "but for" test -- but for the obstacles, Fred would not have fallen over.
For safety and health professionals, it is constructive to have a theory that looks at any factors an organisation can influence to reduce risk, which means considering the whole web of immediate, underlying and root causes.
But people are more complicated than mice, and the issues of what rewards good work practice and punishes bad are complex. Poor behavioural safety programmes treat people like lab mice - a reward for being seen to do the right thing, and a punishment for being caught doing the wrong thing.
Words: Bridget leathleyIn traditional business practice, a cost-benefit analysis would weigh one set of costs against another, giving both equal value – a proportion factor of one. However, if lives rest on one side of the scales, the balance is skewed in favour of safety and a disproportion, or even a gross disproportion, is expected.
Words: Bridget leathleyThe first issue of the journal Ergonomics in 1957 explained its title was derived from the Greek for “the customs, habits or laws of work” and was coined “to denote an approach to the problems of human work and control operations”. During the Second World War, earlier approaches of trying to optimise the armed services’ performance by picking and training recruits to match the demands of the equipment shifted to considering how equipment could be designed to match human capabilities.
ALARP is an abbreviation for “as low as reasonably practicable” and stands at the heart of the way health and safety is managed in the UK.Sections 2 and 3 of the Health and Safety at Work Act require employers and the self-employed to ensure the health and safety of employees and others “so far as is reasonably practicable” (SFAIRP). The Management of Health and Safety at Work Regulations (MHSW 1999) use the term “to the lowest level that is reasonably practicable.”
The judge in a more recent criminal case (R v Chargot, 2008) said employers did not need to consider “trivial or fanciful” risks. Even where prevention would be reasonably practicable, an employer could not be expected to protect against unforeseeable harm.
Words: Bridget leathleyWhereas Burglar Bill has to be assumed to be innocent until proven guilty, under Sections 2 or 3 of the Health and Safety at Work (HSW) Act an organisation is automatically regarded as having failed to ensure the health and safety of employees or others if an accident has occurred. As Lord Hope of Craighead explained in the House of Lords judgment on R v Chargot Ltd: “The onus then passes to the defendant to make good the defence which Section 40 provides on grounds of reasonable practicability.”